Custom Taglets

[Jonathan Gibbons]

On 04/18/2016 09:52 AM, Robert Scholte wrote:
> Hi,
>
> in preparation of the DevoxxFr talk about Maven and Java9 by Hervé 
> Boutemy and Arnaud Héritier I noticed some issues with custom taglets 
> when generation Javadoc reports.
>
> For the developers of Maven plugins we have a set of Annotations or 
> DocletTags[1] to generate the plugin descriptor.
> The taglets are based on com.sun.tools.doclets.Taglet, but when trying 
> to run this with Java 9-ea+113 I get the following exception.
>
> Caused by: org.apache.maven.plugin.MojoExecutionException: An error 
> has occurred in JavaDocs report generation:
> Exit code: 1 - javadoc: error - Error - Exception 
> java.lang.ClassCastException thrown while trying to register Taglet 
> org.apache.maven.tools.plugin.javadoc.MojoAggregatorTypeTaglet...
>
> What's the preferred way to write custom Taglets when using Java9 and 
> will this also work with older versions of Java?
>
> thanks,
> Robert
>
> [1] 
> https://maven.apache.org/components/plugin-tools/maven-plugin-tools-javadoc/

Hi Robert,

javadoc in JDK 9 is affected both by JIgsaw, and by the change to use a 
new doclet API, JEP 221, with a relatively complicated compatibility 
strategy going forward.

http://openjdk.java.net/jeps/221

In this case, it looks like you are using the new version of javadoc, 
with the new standard doclet, but using an old-world Taglet. That should 
definitely be supported, and it looks like a bug that it is not.

I have filed
JDK-8154482: new doclet should support old taglets
https://bugs.openjdk.java.net/browse/JDK-8154482

-- Jon